Food dehydrator



g- 9, 1966 H. F. BUDZiEN 3,264,?53

FOOD DEHYDRATOR Filed Aug. 16, 1963 INVENTOR.

HUGO E 51102 I EN H. F. BUDZIEN FOOD DEHYDRATOR Aug. 9, 1966 2Sheets-Sheet 2 Filed Aug. 16, 1965 INVENTOR. HUGO F BUDZIEN I ATTORNEYSUnited States Patent 3,264,753 FOOD DEHYDRATOR Hugo F. Budzien, Beloit,Wis., assignor to Beloit Corporation, Beloit, Wis., a corporation ofWisconsin Filed Aug. 16, 1963, Ser. No. 302,631 13 Claims. (Cl. 34112)The present invention deals with an improved type of dehydratingassembly particularly applicable for the dehydration of food products,notatably cooked potatoes.

In typical installations for drying mashed potatoes in the preparationof the so-called instan type of packaged product, a substantial amountof manpower is involved in the normal operation, cleaning, and the like.In a typical installation, a single drum is employed for drying, with anumber of individual applicator rolls cooperating with the drum to buildup a layer of mashed potatoes on the periphery of the drum. Frequently,the potato slurry has to be passed from roll to roll by a manualoperation. The potato mash is continuously worked from one roll toanother until a suitable film is built up on the drum for removal by adoctor blade. Much of the difficulty involved in this type of structureis centered about the means employed for spreading the potato mash overthe drying drum in a uniform film.

The present invention provides an improved type of food dehydrator whichsignificantly reduces the amount .of manpower required to provide anacceptable final product. Novel means are provided for spreading thepotato mash over a drying drum to produce a relatively uniform film overthe periphery of the Subsequently, the film on the rotating, heated drumis compacted even further by suitably positioned pressure rolls.Substantial drying capacity is provided in the structure of the presentinvention by the inclusion of an improved air type drier whichcooperates with the drum to remove sufiicient moisture from the film onthe drum so that a doctor blade acting against the surface of the drumremoves the film cleanly in the form of flakes.

More specifically, the present invention involves a drier assemblyincluding a rotating, imperforate drum together with feed means whichare adapted to apply the material to be dried to the periphery of thedrum. Initial compaction of the material applied to the drum is achievedby providing a travelling endless belt which defines with the peripheryof the drum a convergingly shaped gap through which the film of materialadvances during rotation of the drum. Then, one or more pressure rollsfurther compact the film against the surface of the drum, the spacingbetween the succeeding pressure rolls and the drum in the direction ofrotation of the drum being successively smaller. Next, the thus formedfilm on the periphery of the drum passes through a heating zone in whichheated air is applied to the film during its travel through the zone,resulting in the completion of the drying operation on the periphery ofthe Finally, a suitable doctor blade is employed to scrape off the driedfilm from the periphery of the drum and deliver it to a suitableconveying means.

The apparatus of the present invention also includes a novel separatorfor removing lumps from a slurry so that the material fed to theperiphery of the drying drum is as homogeneous as possible. The improvedseparator includes a rotating perforated drum in association withpressure means which urge the incoming slurry against the perforationsof the drum, the pressure means being slightly spaced from the peripheryof the drum to define a passage for oversized lumps which cannot beconveniently accommodated through the perforations of the drum. Theselumps are then directed to a conveyor means which remove them from theassembly, while smaller aggregates appearing in the slurry are forcedthrough the perforations of the drum where an imperforate drum mountedWithin 3,264,753 Patented August 9, 1966 the perforate drum in abutmentwith the inner cylindrical surface thereof presses the slurry enteringthe drum out through the perforations and into a conveyor for deliveryto the drier assembly.

The pressure means in the separator preferably takes the form of asecond perforated drum which rotates in a direction opposite to thefirst named drum so that the slurry entering the space between the twodrums is received through both and is ultimately discharged from theinteriors of the two perforated drums into a common delivery means.

An object of the present invention is to provide an improved drierassembly particularly applicable to the dehydration of food productsand, more specifically, to the drying of mashed potatoes so that theymay be recovered in flaked form.

Still another object of the invention is to provide an improved dryingassembly which substantially reduces the amount of manpower required inoperation particularly in the area of spreading the potato mash over thedrier drum.

Another object of the invention is to provide a drier for mashedpotatoes and the like which is capable of higher operating speeds thanare presently conventionally employed.

A further object of the invention is to provide a combined potatocooker, masher, and drier assembly which produces a more uniform productof higher quality in less time than apparatus previously employed forthis purpose.

Another object of the invention is to provide an improved separator torremoving lumps and the like from a potato mash in a continuous mannerprior to drying.

Other objects and features of the present invention will be apparent tothose skilled in the art from the following specific description of theattached sheets of drawings, which illustrate a preferred embodiment ofthe invention.

In the drawings:

FIGURE 1 is a view partly in elevation and partly i cross-sectionillustrating the drier section of the apparatus of the presentinvention; and

FIGURE 2 is a view in cross-section of the cooker, masher, and lumpremover sections of the assembly which deliver the potato mash to thedrier assembly of FIGURE 1, the view being taken at right angles to theplane of FIGURE 1.

As shown in the drawings:

In FIGURE 1, reference numeral 10 indicates generally a frame supportfor the elements of the apparatus. Rotatably mounted on the frame 10 isan imperforate drying drum 11 composed of cast iron or the like. A steaminput line 12 located centrally of the drum 11 injects steam into theinterior of the drum 11 to bring the surface of the drum to apredetermined drying temperature.

The potato mash is introduced onto the periphery of the drum 11 from aconveyor having flights 13 disposed about a rotating central shaft 14. Asubstantially lump free mash results from the mash being forced througha perforated plate 16 which constitutes the final masherricer of theassembly. The mashed and riced potato mass is then delivered through aconduit 17 onto a spreader conveyor 18 which is longitudinallycoextensive with the drying drum 11. Flights 19 on the conveyor 18distribute the mass along the periphery of the drum 11 through an outletconduit 21.

As the potato mash is deposited on the periphery of the drum 11 itappears as a deposit of varying thickness. The initial compaction of themass takes place by means of an endless belt 22 supported betweensupport rollers 23 and 24. The lower run of the belt 22 defines aconvergingly tapered gap 26 extending the full longitudinal dimen-sion\of the drum 11 and serves to distribute the mass more uniformly alongthe entire longitudinal length and to compact it against the surface ofthe drum 11.v Support rollers 23 and 24 are mounted on shafts 27 and 28.respectivelywhich shafts are received in bearings 29 and 31respectively. The dimensions of the gap 26 are adjustable by supportingthe bearings 29 and 31 in adjustable vertical relation through theagency of spaced guides 32': H

and 33 in which the bearings 29 and 31 are lockedin ad-. justablerelationship with respect to the periphery of the drum 11. Anymaterialadhering to the surface of the belt 22 is removed by means of apair of. doctorblades 36 and 37 disposed in spaced relation along therun of the belt 22. The blades 36 and 37 are secured to? pivot pins 38and 39 respectively, the pins being-secured to arms. 41 and 42 formedwithpslots 46 and 47. Nut

and bolt assemblies 43 and 44 extending through the, slots and the frameprovide for angular adjustment.

or the blades36 and 37 with respect to the belt 22.?

After the initially compacted mass passes through the gap 26, :it issubjected to further compactionby means.

of a driven pressure roller 51 mounted on a shaft 52. The roller 51 isresiliently urged toward the periphery of the drum 11 by springs 53which act against the bearings (not shown) in which the shaft 52 isrotatably, mounted. The gap defined between the periphery of the roller51 and the periphery of the drum 11 somewhat.

less than the smallest dimension of the gap 26:existing between theendless. belt 22and the drum 11 so. that;

further compaction occurs by the pressure of .the roller. 51 against'themass.

10 through a slot 58. I

Further pressure on thernass vbeing dried at the, pe-

riphery of the drum 11 is applied by means of a second pressure roller61 mounted von ashaft 62. The rollerv 51 is resiliently urged toward theperiphery of the drum 11- by means of springs 63. The gap definedbetween the periphery of theroller 61 and the outer periphery of the 1drum 11is smaller thanthev gap defined between the roller, 51 and thedrum so that further compactionoccurs.

' as the drum carries the incompletely driedmass past the;

roller assembly. A doctor blade .64 mounted on a pivot.

pin 66 andadjustably secured to the. frame 10 by means ofv a slot 68 anda stud 67 removes any material that may adhere to the periphery of theroller 61.

The partly dried material after. smoothing compaction by roller 66 thenenters the final drying stage in which most of the remaining moisture isremoved. The drum 11, as indicated in FIGURE 1, carries the filmofpartly. dried material past a perforated wall 69 of a drying. chambergene-rally indicated. at reference numeral 71, the wall 69 having ashape complementary tothe periphery of the drum 11. Heated air isvintroduced into the drying chamber 71 by means of a blower 72 and aninlet duct 73. A damper 74 disposed-within the duct,73

controls the amount of air introduced into the drying chamber 71.

After passingbeyond the end of the perforated wall 69, the film carriedon the drum 11 is substantially dry, and the material is removed in theform of flakes by means of a flake doctor 76 mounted on a pivot pin 77which in turn is carried by an arm having an arcuate slot 78. A nut andbolt 79 secures the doctor 76 is adjustable relation with respect to theperiphery'of the drum 11. It is also possible to advance the doctorassembly in the direction of motion of the drum by providing a series ofapertures 81 for the pivot pin 77, and a series of apertures 82 for thenut and bolt 79 so that the doctor blade assembly may be selectivelypositioned at a variety of positions with respect to the movement of thedrum 11.

The doctor blade scrapes off flakes of the dried mate- Any materialadhering to the roller 51 is removed therefrom by means of a doctorblade 54E mounted on a pivot pin.56" and having a stud 57 whichadjustably locks the doctor blade assembly to the frame rial anddeposits them in a chute 83 at the bottom of whichthere' is} disposedaflake: conveyor, 84 which dc livers the finished material .to;suitablepackaging apparatus.

FIGURE 2 illustrateswa cooking, mashing, and lump separating assemblywhich can be employed in connection with the drier shown in FIGURE 1.The assembly shown in FIGURE 2 includes a frame 86 having a top closure87 through which the raw, sliced potatoes are introduced con-:

tinuously. A .cooking' zone :88. h-aving a conveyor 89 rotatablysupported therein is fed with a suitable source of steam (not, shown). rThe residence time of the potato pair of interengaging toothed .wheels'91 and 92, rotating in opposite directions, mash the cooked potatoes,Where-- upon the .mash-is delivered into-a space 93 existing between apair of oppositely rotating perforated .drums' 94 and 96.= The .space 93is suflicient to define a passage for lumps occurring in the slurrywhich are toolarge to bereceived through the perforations in the drums94 and 96.

These large lumps and any peelings which may remain in the slurry aredropped onto a peeling and lump removal,

conveyor 97 which directs these materials. to a suit-able point ofdisposal. r

Located within the perforate drum 94 is .an'imperforate rotatingcylinder 98, anda similar cylinder 99 is;disposed within ;.the'co11finesof the perforate drum96. The interior cylinders'98" and 99-rotatein thesame direction as the respective drums 4 and 96. Material forced throughthe perforations in the drums is then forced .by the rotating cylinders98 and 99 which abut the inner. diameters of their respective drumsthrough the. perforations and into. a collecting space identified atreferencenurneral 101 where the conveyor flight =13 deliver, the.vmaterial to the drying assembly shown in FIGURE '1- From the foregoing,it will be understood that the dehydrator 'of the present inventionsubstantially reducesthe' manpower required in comparableinstallations,- and produces: an improved quality productat'a fasterrate; It'

should also be evident that various modifications-can be made to thedescribed. embodimentsiwithout departing from the scope of the;presentlinvention.

I claim as my invention:

1.'A drier comprisingla rotating imperforate drum} feedmeanss-arrangedto applya materiaLto be dried to the periphery of said drum, means forheating said drum:

- to thereby forma film'of dried materialon said periphery, a tnavellingendless belt mounted in spaced relation withrespect to the periphery ofsaid drum and formingwith:

said periphery a convergingly shaped gap in the direction of movement ofsaid drum,- said gap coextending longitudinally with said drumyandremoval means disposed be-' yond said 'beltin the'direction of rotationof said drum for scraping the resulting film from said drum.

2. The dn'er of claim 1 which includesat least one press rollintermediate saidlbelt and said removal means, said roll being arrangedto compact the layer onvsaid drum during drying thereof,isaidiroll beingspaced frornsaid drum by an amount which is less than the minimumspacing of said belt from said drum.

3. The drier. assembly of claim 2 including supplementary heating meansdisposed externally of'said drum and positioned intermediate .said pressrolliand said removal means, said supplementary heating means includinga perforated wall in parallel spaced .relationship'to said drum, andmeans for supplying. heated air. through said wall at the film ofmaterial adhering to said drum.

4. The drier of claim 1 which includes adjustable means for varying thespacing between said belt and the periphery of'said drum. v

SJThe drierof claim 4 which includes at least one press rollintermediate said belt and said removal means in the direction 'ofrotation of saiddrum, said press roll being disposed adjacent said drumand spaced therefrom an amount less than the minimum spacing betweensaid belt and said drum.

6. The drier of claim 5 which includes supplementary heating meansdisposed externally of said drum and positioned intermediate said rolland said removal means, said supplementary heating means including aperfovate wall portion in spaced relation to a portion of the peripheryof said drum, and means for supplying heated air through theperforations in said wall.

7. A separator for removing lumps from a slurry comprising a perforatedrotating drum, feed means directing said slurry to the outer peripheryof said drum, pressure means urging said slurry against the perforationsof said drum, said pressure means being slightly spaced from said drumto define a passage for lumps having a size greater than theperforations of said drum, said pressure means urging aggregates of asize not greater than said perforations into the interior of saidperforated drum, collector means adjacent said passage for receivinglumps therefrom, and a rotatable imperforate roll disposed within theinterior of said drum in abutting relationship with the inner peripherythereof, said roll being arranged to rotate in the same direction assaid perforated drum and thereby force portions of said slurry withinsaid drum out through the perforations of said drum.

8. The separator of claim 7 wherein said pressure means comprises asecond perforated drum having its axis in parallel spaced relationshipto the first mentioned drum, said second drum being arranged to rotatein a direction opposite to the first drum, and a second rotatableimperforate roll mounted within said second drum in abutting relationwith the inner periphery thereof, said second roll being arranged torotate in the same direction as said second perforated drum to therebyforce the material received through the perforations of said second drumout of said second perforated drum.

9. An apparatus for removing lumps from slurries and for drying suchslurries comprising a rotating perforated drum, feed means directingsaid slurry to the periphery of said drum, pressure means urging saidslurry against the perforations of said drum, said pressure means beingslightly spaced from said drum to define a passage for lumps having asize greater than can be accommodated by the perforations of saidperforated drum whereby portions of said slurry containing aggregatesnot greater in size than said perforations are forced into the interiorof said perforated drum, collector means adjacent said passage adaptedto receive said lumps for disposal thereof, a rotatable imperforate rollmounter interiorly of said perforated drum in abutment with the innerperiphery thereof to press slurry accumulating within the interior ofsaid drum outwardly through the perforations thereof, a heated, rotatingimperforate drying drum, conveyor means arranged to deliver materialexpressed from said perforate drum onto the periphery of said dryingdrum, a travelling endless belt, a pair of spaced support rollsreceiving said belt therearound, said belt being positioned with respectto said drying drum to provide a convergingly shaped gap in thedirection of rotation of said drum, and removal means disposed beyondsaid belt in the direction of rotation of said drum for scraping theresulting dried film from said drying drum.

10. The assembly of claim 9 which includes at least one press rollintermediate said belt and said removal means, said press roll beingarranged to compact the layer of material on said drying drum, saidpress roll being spaced from said drying drum an amount less than aminimum spacing existing between said belt and said drum.

11. The assembly of claim 10 including supplementary heating meansdisposed externally of said drying drum and positioned intermediate saidpress roll and said removal means, said supplementary heating meansincluding a perforate wall in parallel spaced relationship to a portionof the periphery of said drum and means for supplying heated air throughsaid perforated wall.

12. The assembly of claim 11 which includes adjustable means forpositioning said support rolls with respect to said drier drum andthereby adjusting the spacing between said belt and said drier drum.

13. The assembly of claim 9 wherein said pressure means includes asecond perforated drum disposed in parallel spaced relation to the firstnamed perforated drum and arranged to rotate in the direction oppositeto the first named perforated drum, a second rotating imperforate drumdisposed within the second perforated drum and abutting the innerperiphery thereof, said second imperforate roll being arranged to rotatein the same direction as said second perforated drum to thereby forceslurry contained within the interior of said second perforated drumoutwardly through the perforations thereof.

References Cited by the Examiner UNITED STATES PATENTS 969,955 9/1910Holt 341 12 X 2,102,607 12/1937 Baker 341 12 X 2,566,943 9/1951 King 34l12 3,011,267 12/1961 Stone 34112 WILLIAM F. ODEA, Primary Examiner,

1. A DRIER COMPRISING A ROTATING IMPERFORATE DRUM, FEED MEANS ARRANGEDTO APPLY A MATERIAL TO BE DRIED TO THE PERIPHERY OF SAID DRUM, MEANS FORHEATING SAID DRUM TO THEREBY FORM A FILM OF DRIED MATERIAL ON SAIDPERIPHERY, A TRAVELING ENDLESS BELT MOUNTED IN SAPCED RELATION WITHRESPECT TO THE PERIPHERY OF SAID DRUM AND FORMING WITH SAID PERIPHERY OFCONVERGINGLY SHAPED GAP IN THE DIRECTION OF MOVEMENT OF SAID DRUM, SAIDGAP COEXTENSING LONGITUDINALLY WITH SAID DRUM, AND REMOVAL MEANSDISPOSED BEYOND SAID BELT IN THE DIRECTION OF ROATION OF SAID DRUM FORSCRAPING THE RESULTING FILM FROM SAID DRUM.